Technical Field
The present invention relates to a detecting device, and in particular it relates to an apparatus for detecting the liquid level.
Background
Liquid level sensors and level sensors are widely used in various fields. For example, a level sensor can be applied in a rain gauge, to monitor rainfall. In addition, a liquid level sensor can also be used in the medical field. For example, a liquid level sensor can be used in a container containing an intravenous injection solution to monitor the flow or speed of the intravenous injection, and it provides information to health care providers.
One traditional liquid level sensor determines the liquid level using image identification technology, as shown in U.S. Pat. No. 7,982,201. Another traditional liquid level sensor uses ultrasound detecting technology to determine the liquid level, as described in U.S. Pat. No. 4,610,164. However, theses traditional liquid level sensors are expensive and complicated, and are no user-friendly nor easy to use. Furthermore, another traditional liquid level detecting mechanism is implemented by using an electrode to come in direct contact with the liquid level, but the invasive detection mechanism cannot maintain sterility and therefore it cannot be used in medical equipment.